Vacuum engine



Allg. 30, 1932. f R D CONKLlN `1,874,454

VACUUM ENGINEv Filed April 9, 1951 2 Sheets-Sheet 1 INVENTOR- R0 0e D. C nK/ln A'ug. 30, 1932.

R. D. CONKLIN Filed April 9, 1931 VACUUM ENGINE 2 Sheets-Sheet 2 INVENTOR Roseau 7.62m Kla'n ATToRNEY Patented Aug. 30, 1932 i UNITED ASTATES PATENT ori-'TCE ROSCOE D. CONKLIN, OF RAHWAY, NEW JERSEY, ASSIGNOR TO NATIONAL PNEUMATTC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF V'WEST VIRGNIA VACUUM Application led April 9,V

VThis invention relates in general to improvements in vacuum engines7 more particularly in the differential type.

One of the objects of this invention is to provide a differential vacuum engine which is exceedingly simple in structure and of rugged form.

Another object of this invention is to provide a differential vacuum engine with auto- 10, matic cushioning means for retarding the stroke of the engine for each end of its movement.

A further object of this invention involves a pistonconstruction in which the cushioning means forms a part thereof.

A still further object of this invention is to provide cushioning means in an engine of this type which automatically resets itself for operation to cushion the engine near the end of its stroke in either direction.

A still further object of the invention is the provision of a cushioning means which automatically sets itself for cushioning the engine in the direction in which it is travelling.

These and many other objects as will appear from the following disclosure are secured by means of this invention.

This invention resides substantially in the combination, construction, arrangement and relative location of parts, all as will be set forth in greater detail hereinafter.

Referring to the drawings- Fig. l is a view with some parts in vertical longitudinal cross section and others broken away of the engine of this invention;

Fig. 2 is a right hand end elevational view vof the engine and its supporting means.

Fig. 3 is a diagrammatic view of a vacuum source, the engine of this invention and a control valve in the connection between the two.

Fig. 4 is a horizontal cross-sectional view through the valve employed in the system of this invention;

Fig. 5 is a vertical cross-sectional view through one of the check valves employed on the engine.

The engine comprises two cylinders, A and B united together in longitudinal align- ENGINE 1931. Serial No. 528,742.

. ment by means of a ring C. and screws for securing the parts together as shown in Fig. l. The opposite ends of the cylinder are provided with end walls as shown. Near the Y center of the cylinders at the top thereof, isr

a longitudinal slot l). and the ring C. is likewise provided with a slot E. Each end of this cylinder construction is supported in a bracket F. which is provided with a right angle foot flange Gr. T he end brackets F. are' provided with spaced ears H. through which you extend the longitudinal rods I. The end brackets F. are secured to any suitable support and the cylinder is held in place by the tie rods I which are secured in the ears by means of nuts. The left hand cylinder wall of cylinder A. is provided with a threaded port formed in the pipe receiving collar J. The port where it enters into the cylinder is restricted as shown at K. A similar coupling collar L. is provided for the right hand cylinder B. but in this case, the port into the cylinder is not restricted. At M. is a wall member provided with annular flanges internally threaded and with the coupling member N. which moves in the slots D. and E. The engine is coupled with the object to be operated such as a door by means of the member N. i

Secured in the internally threaded flanges of the member N. are the smaller cylinders O. and P. which are likewise closed with end walls S. The end walls S. are provided with ports S and av central flanged hole as shown.

At T. and U. are pistons for the cylinders A. and B, which are secured to or formed integral with the smaller cylinders O and P. which act as piston rods for these pistons. Suitable flexible cups T and U made of leather, for example, are secured to the pistons P. and U. by means of the annular members T and U. These members T and U are formed with an annular recess as shown within which a suitable oil absorbing material Ta and U2L such as felt is secured. Within the smaller cylinders O. and P. are the smaller pistons G. and R. which are provided with the piston rods V. and W. in the form of tubes. The ends V and W are notched as shown' at Ve and We. To the pistons G. and Y R. are secured the leather cups Vd and Wd. These leather cups are secured in place by means of the discs having the central sleeves V and Wa and the annular discs Vb and Wb. The discs Vb and lV are shaped to form an annular channel in Which the oil absorbing means Vc and W'3 are mounted. The `right hand end of cylinder B is exactly the, same as the left hand end of cylinder A With the sole exception that theport into cylinder B is not restricted as istheY case of the port K into cylinder A. The structure of the parts carried by M is also the sameon each side thereof as shovvnA in section at the left end and in elevation at the right end.

Inithe memberM. are providedthe in fclined'oil channels l and 2 closed bymeansof the lplugs-33nd 4. These channels l and y2 open intothe cylinders C). `and P. by'means'of 'which' oil may be introduced thereinto. Like- VWise inthe member N. are the passages and 5. The passage 5 opens into cylinder Pfand the other kpassage 5, opens into cylinder .0.

- The passages 5 and 5 emerge vat the lower edge of member M and are provided with check valves 6 and 6 respectively constructed as shown in Fig. 5. Each check valve is of'the "ball type and of the same construction.

epa

VValve/6 is shown in detail in Fig. 5 as comprising a body having a chamber `8 closed by a plug 10 having a central bore 11 passing therethrough.' The inner end of ther plug 10 is provided with a conical seat 10 While the upper end of chamber 8 also forms al con- :ical seat 8. `A ball 9 in chamber 8 may rest on seat l0,to close passage ll or onseat 8 to close passage 8a which opens mtopasysage 5. 'Chamber 8 opens tothe atmospherel through the restricted passage 7 `between seats 8-and .10. -Referring to Fig. 3, the engine 1s Shown connectedto a vacuum source 20 through av =pipe 2l, a Way valve 22 and the pipes 24 and 25 Which open into the cylinders A. and vB. `respectively. Valve 22 is operated by the ylever 23 and is provided With-the exhaust Lpipe 26.

The valve 22 is shown in detail in'Fig. 4

to'aidin yunderstanding the operation ofi the motor and system of this invention although :the valve luy-itself forms no part of the invention. The valve comprises a casing having the fourv pipe connections 21, 24 25 and 26 of Fig. 3. Within the casing is the. mov- `able part 22 of the valve provided with l passages .22a and 22b and the handle 23. In lposition A pipes 21 and 24 are connectedlby passages 22L .andfpipes 25 and 26 are con-'fr -nected by passage 22h. In position Capi es '24 and 26 are connected by passage 22a (lindicatedby dotted lines) and pipes 21l and'. 25

are .connected by passage 22b (indicatedby dotted lines) The'operation of the engine will nov7 be de-f; scribed. It -will be assumed that with 'the s.

parts at the extreme left, as shown in the various figures, that the part to be operated by the engine, such as a door for example, is at the extreme left hand of its movement. In the case of a door, it will be assumed that Ythe-door is closedk in thisposition of the parts.

As is apparent :from Fig. 1 andthe kprevious description, member M and all the arts attached thereto including N, 6, 6', O, T and U 'with their attached `parts Aform a unit and move together. rPistons Gand R and their attached parts including V and W are supported by that unit but move with or with respect thereto depending upon pressure conditions Within the device.

Referringto Fig..1 piston R. and the parts 'connected thereto, would normally be at the extreme leftin cylindery P. that is against the `member M. When Avalve 22 is operated to connect pipes21iand 25, pipes 24 and 26 will be connected. `The vacuum source 20 is then connected to cylinder B. and cylinder A. is connected to the atmosphere. The result is kthat kthe member .M. and all the parts connected thereto begin tomove to the right. At f `seat sufliciently'to let-atmospheric pressure npassthroughpassages 11 and 5 into cylinder l. tothe left of piston R.

This piston :R'will ,continue to move to the right With respect to cylinder P. until its sleeve We strikes-thel end wall of the cylinder P. Thispositionof piston R. and its connected pa-rtsis shown in Figure l. When all of the movingparts have moved to the :right to the point Wherey the projecting piston :rod 2W. engages the end Wall of cylinder B.

piston R. will'stop while all of the other moving parts ofthe enginewill continue in their movement to the right. As a result the air in cylinder.P.fbehind.-piston Rfis trapped p since; the ball,9 will fall back on its lseat to yclose* passage 11. The ytrappDed air can then only escape :from cylinder through pas- A5 .and 8V andE the restricted port 7 The resualtfisJthatfor-the remainder of the stroke ofthefmainipartso thefengine, they will be cushioned and slowed down in their movement'sathattheengine '.Willapproach the end ot the strokezat -areduced speed.

To effect the operation off the parts in the 'opposite'zdirection, thatnis to the Ieft in the 41figures;valve 22 :is operated to connect pipes 21 and 24 and 25 and 26. The operation of theenginewill then lbe substantially the same exceptthlat all of the parts will move more' slowly to the left because of the restricted port K. In this case piston G. and its connected parts will move to the lett within cylinder O. because the vacuum source which is connected to cylinder A. is also connected to the interior of cylinder O. through the ports S. The other check valve with the ball 9 which is now shown, will permit atmospheric pressure to enter cylinder 0. behind piston (x.

` The operations are the same as previously described, except as stated, the parts will move more slowly in the opposite direction which, in the case of a door, would be door closing direction.

It will be apparent from the above disclosure that this invention resides in certain principles ot construction and operation which may be embodied in other physical forms and carried out in other ways without departure therefrom, and I do not, therefore, desire to be strictly limited to the disclosure as given Jfor purposes of illustration, but rather to the scope ot the appended claims.

What I seek to secure by United States Letters Patent is:

l. In a vacuum engine of the type described, the combination comprising a cylinder, two pistons mounted in said cylinder, hollow piston rods uniting said pistons, means to separate the hollow piston rods into two chambers, pistons mounted solely in the chambers, and valve means for permitting the introduction of air into said chambers behind the pistons.

2. An engine of the type described, comprising a cylinder having ports at each end, said cylinder having an opening intermediate its ends, pistons in said cylinder, hollow piston rods uniting said pistons in a rigid unit, means to separate the hollow piston rods into two chambers, pistons in said chambers having piston rods movable to the exterior thereoit, and check valves controlling passages opening into the piston rod chambers.

3. A vacuum engine of the type described, comprising a cylinder closed at both ends and provided with a port at each end, said cyl- 'nder being open intermediate its ends, two pistons in said cylinder, a hollow piston rod connecting said pistons into a rigid unit, means for dividing the hollow piston rod into separate chambers, a piston in each off' said chambers, each having a piston rod, each chamber having a passage connecting it with the atmosphere, and a ball check valve in said passage.

4. A vacuum engine of the type described, comprising a cylinder closed at both ends and provided with a port at each end, said cylinder being open intermediate its ends, two pistons in said cylinder, a hollow piston rod connecting said pistons into a rigid unit and divided into separate chambers, a piston in each of said chambers, each having a piston rod, each chamber havinga passage connecting it with the atmosphere, and a ball-check valve in said passage', each ot said valves'having a restricted bj1-pass.

5. An engine' of the type described, comprising cylinder closed at er ch end and provided with a port, by means ot which the cylinder may be alternately connected to a vacuum source, said cylinder being open intermediate its ends, pistons in said cylinder, a hollow piston rod uniting the pistons in a rigidy unit and forming substantially'elosed chambers having end walls, each ot the pistons said chambers having a piston rod slidable through an opening in the end wall orp the closed cnamber, and ball check valves controlling a passage opening into said chambers be iind the pistons therein.

6. An engine of the type described, comprising a closed cylinder having a port at each end and having an opening intermediate its ends, two pistons in said cylinder, two smaller cylinders united at their inner ends by a coupling member, said smaller cylinders having walls at their other ends with central openings and said pistons mounted one on each smaller cylinder, pistons in said smaller cylinders having piston rods slidable through the central openings ot the end walls, two passages insaid coupling member, one opening into one or" the smaller cylinders and the other opening into the other of the smaller cylinders, and check valves mounted on said coupling member :tor controlling said passages.

7. An engine ot the type described, comprising a closed cylinder' having a. port at each end and having an opening intermediate its ends, two pistons in said lcylinder, two smaller cylinders united at their inner ends by a coupling member, said smaller cylinders having walls at their other ends with central openings, and said pistons secured one to each smaller cylinder, pistons in said smaller cylinders having piston rods slidable through the central openings or the end walls, two passages in said coupling member, one opening int-o one of the smaller cylinders and the other opening into the other ot the smaller cylinders, and ball check valves mounted on said coupling member for controlling said passages, cach of said ball check valves having a restricted by-pass connecting the passages with the atmosphere between the ball check valves and the spaces within the small cylinders.

8. in engine of the types described, coinprising a. closed cylinder having a port at each end and having an opening yintermediate its ends, two pistons in said cylinder, two smaller cylinders united at their inner ends by coupling member, said smaller cylinders having walls at their other ends with central openings and having said pistons attached thereto, pistons in said smaller cylinders having piston rods slidable through the central openings of the end walls, two passages.- in saidcoupling member, one opening into one of the smaller cylinders and the other opening into the other of the smaller cylinder, and ball check valves mounted on said coupling member for controlling said passa/ges, said ball check valves being unseated by atmospheric pressure to supply atmosp'heric pressure into the small cylinders when unseated.- c

-9, A vacuum engine as described comprising two connected cylinders, connected pistons within said cylinders, cushioning means mounted on said pistons operable to cushioning position in the direction of movement 0f the piston initiallyupon connection to the vacuum source and means for supplying air at atmospheric pressure to the cushioning means initially upon connection to the vacuum source.

In testimony whereof I have hereunto set my hand on this 7th day of April A. D., 1931.

f ROSCOE D. CONKLIN. 

